Chapter II
1.
GENERAL INSTRUCTIONS
You have just acquired an intrincally safe portable digital multimeter and we thank you for
your confidence.
This intrinsically safe multimeter enables electrical measurement in explosive
atmospheres in intrinsically safe circuits (gas per group II C, temperature class T6) in
potential danger zones (zone 1) and in gassy mines (group I). In accordance with the
standard, the certification allows voltage measurements up to 60 V and current
measurements up to 500 mA. It complies with the rules defined in harmonised
European standards NF EN 50014 and NF EN 50020 (electrical equipment for
explosive atmospheres).
For your own safety and that of the unit, you must observe the instructions described in this
manual to ensure safe operation of the multimeter, in the specified conditions of use.
1.1.
Precautions and safety measures
The safe use of equipment in danger zones requires familiarity with the group of gases and
comparison of the self-ignition temperature of the gas mixtures involved with the temperature
indicated on the equipment.
This multimeter must be used only by personnel who are familiar with the rules for explosive
atmosphere equipment and have undergone appropriate training.
1.1.1. Utilisation of the intrinsically safe multimeter in danger zones
The MX 57 EX multimeter may be used for short measurement operations on
category " ib " intrinsically safe circuits. " "Short" means that the multimeter must
not be used continuously, nor be used as a fixed unit.
The MX 57 EX multimeter may be considered as a passive element without
energy accumulator, i.e. with no inductance lint ≈ 0, or capacitance Cint ≈ 0.
During a voltage measurement, to prevent any overload, the existing intrinsically
safe safety circuit must never be opened.
1.1.2. Before use
∗
The measurement terminals can be connected only to an intrinsically safe circuit.
∗
The electrical parameters of the intrinsically safe circuit must comply with the following
values :
∗
After an unauthorized utilisation of circuits other than intrinsically safe circuits, the user
must make certain, with a certified organisation, that the multimeter is still compliant.
∗ For your own safety, only use the measuring probes which have been delivered with the
instrument. Before use, check that they are in good condition.
∗
In an explosive atmosphere, use only accessories that have a certificate of conformity
authorising their use with this multimeter.
∗
Never exceed the protective limiting values given in the specifications, in particular
those concerning intrinsic safety. Use the instrument exclusively on an intrinsically
safe circuit.
∗
A special intrinsic safety case ensures IP 67 sealing.
Intrincally safe portable digital multimeter
U ≤ 60 V (peak value) or I ≤ 500 mA
X02137A00 - Ed. 1 - 12/01
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